Although a silicon-based electrode is a promising candidate as anode in Li-ion batteries, repeated cycling results in significant morphological changes of the silicon particles leading to formation of highly porous silicon structures. We applied small-angle neutron scattering (SANS) with selective contrast matching to provide quantitative insights into the solid-electrolyte-interphase (SEI)...
A new multianalyzer Bambus is being constructed at Panda, MLZ. The objective is to construct broad reciprocal space maps at multiple energy transfers, in order to get insights of broad features at low energy or study complex dispersion laws. Because this spectrometer is designed as a complementary option to the normal TAS mode, a fast switch between the two setups is foreseen. The general...
Major instrument upgrades at DNS, including a new Fe/Si supermirror based focusing polarizing bender, and a 300 Hz disc chopper system, have been accomplished recently. This has opened up possibilities to combine polarized neutrons with time-of-flight spectroscopy for the studies of exotic magnetic order and excitations in emergent quantum materials. In this poster, an overview about those...
The MLZ provides a number of different instruments – tailored to different scientific problems – to scientists from all over the world.
As control-suite NICOS is established, providing a common user interface with scripting capabilities and data collection. The hardware abstraction is mostly implemented in 'entangle', a TANGO device server written in Python, but also EPICS, SECoP, and selected...
KOMPASS is a polarized cold-neutron three axes spectrometer currently undergoing its final construction phase at the MLZ in Garching. The instrument is designed to exclusively work with polarized neutrons and optimized for zero-field spherical neutron polarization analysis.
[1] M.Janoschek et al., NIMA 613 (2010) 119
[2] A.C.Komarek et al., NIMA 647 (2011) 63
The construction of KOMPASS is...
Influence of pressure on the formation of mesoglobules of the thermoresponsive polymer poly(N-isopropyl acrylamide) (PNIPAM) in aqueous solution, when heated above its cloud point is investigated using very small angle neutron scattering. At a critical pressure, a remarkable increase in the size of PNIPAM mesoglobules is noted. We presume that the observed increase in the size of mesoglobules...
In addition to the “normal triple axis” mode, PUMA is equipped with the multi-analyzer setup consisting of 11 arbitrarily configurable analyzer-detector channels suited for kinetic experiments to realize an entire (Q,E)-scan in a single shot. Moreover, the same setup can be used also for polarization experiments to determine the spin flip and the non-spin flip components simultaneously at the...
Investigations of magnetic excitations focus on new magnetic materials, quantum magnetism, superconductivity, heavy-fermion or low-dimensional systems, frustrated and multiferroic materials. PANDA, being a high-resolution, high-flux cold TAS spectrometer with a remarkably low background, successfully contributes with high-level experiments to a broad variety of these scientific topics. We here...
PUMA is optimally designed for measuring inelastic neutron scattering which covers a wide energy and momentum range. Owing to high thermal-neutron flux at FRM-II, PUMA is recognized as one of the most powerful thermal neutron TAS. This attracts various user community groups to conduct challenging measurements on PUMA such as magnetic fluctuations in unconventional superconductors or spin-waves...
Poly(2-alkyl-2-oxazoline) molecular brushes, featuring PMeOx-b-PBuOx side arms, are investigated in aqueous solution. While hydrophobic PBuOx is attached to the backbone, storing the anticancer drug, Paclitaxel, the hydrophilic PMeOx is at the periphery, facilitating transport in water. With small-angle neutron scattering, the structure of the PTX-loaded molecular brushes with different...
Stimuli-responsive physical hydrogels change their properties upon a small change of the environment and may be used as fast sensors, for drug delivery or for tissue engineering. In this work, we investigate the telechelic pentablock terpolymer P(n-BuMA-co-TEGMA)-b-PDMAEMA-b-PEG-b-PDMAEMA-b-P(n-BuMA-co-TEGMA) in dilute aqueous solution as a function of temperature and pH using small-angle...
Compared to poly(N-isopropylacrylamide) PNIPAM, poly(N-isopropylmethacrylamide) PNIPMAM shows different behavior, though it has a similar chemical structure, only with additional methyl groups on the backbone, e.g. a higher transition temperature (43 °C instead of 32 °C). We studied the temperature-dependent phase behavior of PNIPMAM in D2O using small-angle neutron scattering. Different from...
Using quasi-elastic neutron scattering, we study the pressure-dependent hydration behavior of an aqueous poly(N-isopropylacrylamide) solution during heating through its cloud point (CP). At high pressure, the hydration water diffuses more rapidly than at low pressure, which indicates enhanced hydrophobic hydration. An abrupt dehydration, mainly of the hydrophobic groups, is observed at the CP...
